I'm baffled by this one, and I sure would
appreciate your thoughts on this phenomenon. The motor is a very low
hour Mercury/Force 90 HP three cylinder, triple carbs in a 1994 Regal
"Rush" jet boat. It seems that when the battery is really
totally charged up, it will start instantly, but if the battery is even a
little down, as after allowing the boat to sit idle for a week, the motor
will crank like crazy, but not start...and...the bigger problem is that
you can hear a loud metallic knocking...like as though the starter bendix
was slamming the starter gear into the ring gear and then dropping off,
and then hitting it again, repeatedly. The banging rate is at least
once or twice per second, and through all of this, the motor is cranking
quite fast...like it should start easily. Do you have any idea what
the real cause of the banging may be, and why the no-start, and how to
correct it?
Thanks so very much for your help.
Jim

Jim,

Sounds like the prime system is not working. That is why it doesn't start.
The banging is the bendix working the flywheel during the compression
stroke. Nothing to worry about.

Randy

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